PSEUDOMEMBRANOUS COLITIS Flashcards
what is pseudomembranous colitis AKA?
clostridium difficile- induced diarrhea
what is pseudomembranous colitis?
inflammation of colonic mucosa caused by toxins released by bacterium Clostridioides difficile, previouslt known s Clostridium difficile
what are the majority of cases of pseudomembranous colitis d/t?
majority are hospital acquired
community acquired are increasing- 40%
what kind of bacteria is clostridioides difficile?
gram- positive, obligate anaerobe
obligate= needs no O2
what 2 forms does clostridioides difficile exist in?
- spore from
- vegetative from
what is the spore form of clostridioides difficile?
outside the colon; resistant to heat, acid, and abx
what is the vegetative form of clostridioides difficile?
in the intestine
how are spores of clostridioides difficile transmitted?
via fecal-oral route
is clostridioides difficile contagious?
HIGHLY
what id the #1 RF of clostridioides difficile?
recent abx use
- clinda
- ceph 3rd and 4th gen -> cefipime, cefdinir, ceftriaxone
- fluoroquinolones ->floxacin
what are the other RF of clostridioides difficile?
prior episodes of c. diff
advanced age >65
hospitalization
nursing home resident
severe medical comorbidities
use of PPI & H2 Blockers (gastric-acid suppression)
chemo
what is the pathogenesis of clostridioides difficile?
disruption of normal flora using abx leads to overgrowth of c. diff
intestinal damage is d/t toxin release : enterotoxin A and cytotoxin B
what is the epidemiology of clostridioides difficile?
5% healthy adults colonized
8-10% hospitalized adults colonized -> i think this means they have it w/no sx
what is enterotoxin A?
targets brush border enzymes that leads to altered fluid secretion (watery diarrhea)
what is cYtotoxin b?
10x more potent
disrupts cytoskeleton of enterocytes leading to apoptosis (pseudomembranous colitis) -> inflammation
what is the clinical presentation of non-fulminant colitis?
- foul smelling, watery diarrhea that is rarely bloody
- cramping abdominal pain
- Fever
- N/V Rare
what is the clinical presentation of fulminant colitis?
- significant systemic toxic effects
- acute abd pain w/ distention
- signs of sepsis- hypotension
- tachycardia
- change in mental status
- toxic megacolon: large bowel dilation >7 cm; cecum >12 cm
- colonic perforation, ischemia, and necrosis
when should c. diff be suspected?
suspect c. diff in any patient who has developed diarrhea within 2 months of abx use or 72-hrs of hospital admission
when should stool testing be done?
only in sx patients
what are the 2 dx tests for c. diff?
- enzyme immunoassay (EIA) for c. diff antigen
- EIA for c. diff toxins A and B
- nucleic acid amplification test using polymerase chain rxn (PCR) for c. diff toxin gene
what is entailed in the enzyme immunoassay (EIA) for c. diff antigen?
looking for glutamate dehydrogenase antigen (GDH)
rapid test thats widely available
+ results confirms presence of organism, but not if it is toxigenic
what happens after successful tx of c. diff in regards to rhe nucleic acid amp PCR test?
that test can remain positive after successful tx
what will blood testing show in someone w/ C. diff?
leukocytosis (often >20k)
significant bandemia w/ fulminant colitis
hypokalemia d/t diarrhea
what will an abd x-ray show in c. diff?
can show colonic dilation
free air in case of perforation
